The amount of water needed for landscapes depends on three decisions: soil management, plant choice and irrigation method. Water conservation starts with soil health. Deep roots and biologically active soil provide greater moisture retention and thus allow longer duration between irrigation. Semiannual soil amendment with compost and mulch is recommended.

Deep-rooted native plants can withstand fairly long dry periods but do benefit from occasional summer irrigation. Turf, with shallow roots and frequent cutting, requires considerable irrigation, 4 to 10 times more than longer native grasses.

Spray irrigation is typically only 60% efficient, while drip or subsurface irrigation is 95% efficient. Beautiful palettes of climate suitable plants are available for replacing lawns. There are multiple benefits of native plants compared with the monoculture of turf: less water, less maintenance, less creek-polluting fertilizer and pesticides, greater scenic variation and biodiversity, and greater sustainability for all.

Change Irrigation Schedule Monthly

A plant's irrigation requirements depend on the weather, specifically the amount of daylight, temperature, wind and humidity. Below is a graph showing the irrigation needs through the year based on evaportransipiration (ET).